PSLE At a walkathon, each participant completed either a 2-km route, a 4-km route or a 5-km route.
16 of the participants completed the 2-km route,
34 of the participants completed the 4-km route and the rest completed the 5-km route. For every 1 km a participant walked, $10 was donated to charity. A total of $5400 was donated to charity.
- What is the ratio of the number of participants who completed the 2-km route to the number who completed the 4-km route to the number who completed the 5-km route?
- What is the total number of participants at the walkathon?
(a)
Fraction of the participants who completed 5-km route
= 1 -
16 -
34 = 1 -
212 -
912= 1 -
1112 =
112 Ratio of participants who completed the different routes
2 km : 4 km : 5 km
2 : 9 : 1
(b)
For every 1 km a participant walked, $10 was donated to charity.
Total distance covered by the participants
= 5400 ÷ 10
= 540 km
|
2-km |
4-km |
5-km |
Total |
Number |
2 u |
9 u |
1 u |
12 u |
Value |
2 |
4 |
5 |
|
Total value |
4 u |
36 u |
5 u |
|
Total distance that the participants covered
= 2 x 2 u + 4 x 9 u + 5 x 1 u
= 4 u + 36 u + 5 u
= 45 u
45 u = 540
1 u = 540 ÷ 45 = 12
Total number of participants
= 2 u + 9 u + 1 u
= 12 u
= 12 x 12
= 144
Answer(s): (a) 2 : 9 : 1; (b) 144